1. Field of the Invention
The present invention relates to a very small aperture terminal (VSAT), and in particular, to a VSAT with a dual-input DC power control.
2. Description of the Related Art
A VSAT satellite communicator transmits and receives signals through a mini-antenna, transferring video and audio information through high bandwidth connections provided within range of the satellite signal. Currently satellite networking services are highly developed so that various application services are popular. Portable satellite communication devices are widely used, with the result that low power consumption is a priority.
Although signal transfer systems in electronic circuits are minimized, considerable power is required to enable radio transmission. Thus a power amplifier provides amplification necessary for the minimized circuits to provide radio waves of sufficient power.
The power amplifier magnifies an input signal for output, such that power used is often several times larger than that in electronic circuits. Thus, reducing power consumption of the power amplifier and control thereof by a power switch, is desirable.
A low noise high frequency signal source is used in uplink design, whereby a phase lock loop oscillator (PLO) stabilizes an inaccurately operating high-frequency signal. In comparison to a frequency multiplier, PLO has lower cost and higher performance.
In addition, a mechanism for controlling VSAT operations is required.